The Dallas Cowboys are 6-1 and riding high atop the NFC, but things are going to get a bit more difficult now. The Cowboys' defense, which has been led so far by the surprisingly effective play of its secondary, is about to lose two starters.

Safety Barry Church and cornerback Morris Claiborne are expected to miss the next four to six weeks due to injuries sustained during the team's win over the division rival Philadelphia Eagles on Sunday night. Church broke his forearm while Claiborne sustained a groin injury that may or may not be a sports hernia.

"I'm going to just say in both cases we're probably looking at anywhere from a month to six weeks," Cowboys owner/general manager Jerry Jones said during a radio interview with CBS affiliate 105.3 The Fan. "But that's just really a guesstimate."

Both Church and Claiborne are in the midst of their best professional seasons. Church has teamed with second-year man Byron Jones to form a very effective safety duo, with Church as the box safety and Jones moving all over the field. He has been extremely effective in helping fill running lanes, but has also shown improved coverage abilities, intercepting two passes and knocking down another.

Claiborne, meanwhile, has been considered a massive bust for the Cowboys but was finally breaking out in his fifth season. He's been starting across from Brandon Carr all season and has been playing about 90 percent of the snaps, per Pro Football Focus. After four seasons during which he allowed 130 catches for 1,875 yards and 10 touchdowns (on 200 targets) and yielded a passer rating of 105.7 on throws in his direction, Claiborne has allowed only 26 catches for 214 yards and a score (on 48 targets) with an opponent's passer rating of only 64.1 in 2016. That's the 12th-best figure among the 112 cornerbacks that have been on the field for at least 100 passing snaps this season.

In their absences, J.J. Wilcox (safety) and rookie Anthony Brown (cornerback) will likely take over larger roles in the secondary. Jeff Heath will presumably see more sub package work as well. Given the Cowboys' pass rush deficiencies (31st in pressure rate so far this season), the play of their secondary is extremely important. They're about to be working shorthanded for awhile.